Answer:
Option A. 11
Explanation:
The atomic number of an element does not change.
Recall:
Atomic number = proton number
If the atom is neutral, then,
Proton number = electron number
Since the element is sodium, then, the atomic number of sodium–25 is 11.
Also, we were told to obtain the electrons of a neutral atom of sodium–25
Therefore,
Atomic number = proton number = 11
Since the atom is neutral,
Proton number = electron number = 11
Answer:
22.02 m
Explanation:
given,
Force, F = 107 N
angle made with horizontal = 13.5◦
Power develop by the lawn roller = 69.4 W
time = 33 s
distance = ?
Force along horizontal= F cos θ
= 107 cos 13.5°= 104 N
Power = 
69.4 = 
W = 2290.2 J
Work done= Force x displacement
displacement= 
= 22.02 m
Answer:
i Guess 1 or 3
Explanation:
yea 1 or 3 or just guess hard
Not sure what you mean by "breaks in the tension" but I suspect you mean the rope will come apart if the tension in the rope exceeds 1800 N.
In the free body diagram for the 500 N weight, we have a figure Y with the net force equations
• horizontal net force:
∑ F[hor] = T₁ cos(θ) - T₂ cos(θ) = 0
• vertical net force:
∑ F[ver] = T₁ sin(θ) + T₂ sin(θ) - 500 N = 0
From the first equation, it follows that T₁ = T₂, so I'll denote their magnitude by T alone. From the second equation, we have
2 T sin(θ) = 500 N
and if the maximum permissible tension is T = 1800 N, it follows that
sin(θ) = (500 N) / (3600 N) ⇒ θ = arcsin(5/36) ≈ 7.9°
is the smallest angle the rope can make with the horizontal.
